Patent Literature 1 listed below discloses a technique applying to a compressor a high-frequency voltage of a frequency higher than a frequency at which an inverter drives the compressor, such that the compressor is heated at the high-frequency voltage (hereinafter referred to as “high-frequency heating”) to eliminate refrigerant retention (so-called “stagnation”) in the compressor.
A plurality of switching elements are installed in the inverter. When the switching elements are mounted as chips, the larger chip area reduces the yield. The smaller chip area improves the yield in the removal from the wafer, thereby achieving the price reduction.